Brake drum



Jan, 16, 1934. s M UDALE 1,943,641

BRAKE DRUM Filed July 26, 1930 Patented Jan. 16, 1934 UNITED STATESPATENT OFFICE BRAKE DRUM Michigan Application July 26,1930. Serial No.471,004

4 Claims.

This invention relates to brake drums for motor vehicles.

The object of this invention is to permit the brake drum to expand underthe action of heat 5 without distortion so that the brake drum remainstruly cylindrical.

Brake drums of the prior art have been defective in that they assume theconical form.

The second object of this invention is to construct in one piece a brakedrum which will remain cylindrical instead of using a two or three piececonstruction as has been done heretofore. The final object of thisinvention is to utilize the recently available (due to the introductionof electric furnaces) cast iron having high tensile strength andexcellent wearing qualities. This cast iron has also the ability towithstand a moderate amount of heat and is intermediate in its qualitiesbetween malleable iron and ordinary 2o gray iron, having the wearingqualities of the latter and'the strength of the former.

Figure 1 shows the brake drum in elevation.

Figure 2 shows a cross section on plane 2-2 of Figure 1.

In the figures, A refers to the brake drum proper; B is a stiffeningflange on the open end; and CC are a number of ribs connecting theflange B with the drum A.

The drum A is provided with a flange D on its inner edge. Extending fromthis flange D are the arms E, F, G, H, J, K. These arms are providedwith bolt holes MM at their inner ends. These bolt holes are the meanswhereby the drum is supported on the hub of the wheel.

Operation When this brake drum is in use, the drum A expands and thetendency of the hub to remain cooler than the drum causes the holes MMto is to place a strain between M and the drum A. By making the arms E,F, G, H, J, K, of the shape shown, and reenforcing the drum A by theflanges B and D and the rib C, the tendency of the strain exerted by thebolt holes MM to distort the drum A is resisted and the drum A remainssubstantially cylindrical.

What I claim is:

p l. A one-piece internal cast iron brake drum for motor vehiclescomprising a braking, cylindrical portion having yieldable arms castintegral therewith, means at the inner ends of said arms for supportingsaid brake drum.

2. A one piece internal'cast iron brake drum for vehicles comprising aring providing a cylindrical braking surface and a flange extendingtherefrom, bolt holes in said flange, said flange being cut away betweenthe bolt holes substantially up to said ring, external cooling meansdistributed over the outside or" said ring and concentrated toward theopen end thereof so as to counteract the tendency of said cylindricalbraking surface to become bell mouthed.

3. A one piece internal cast iron brake drum for vehicles including aring providing a cylin- 0 drical braking surface and an inwardlydirected flange portion provided at the inner edge thereof with openingsfor the reception of securing means, said flange portion being cut awaybetween said openings towards and approximately to said ring. 35

4. An integral cast metal drum for internal brakes including a ringproviding an internal cylindrical braking surface and a radiallyinwardly directed flange portion having openings for securing meansadjacent the radially inner edge thereof, said flange portion being cutaway between said openings whereby to form arms of a length greater thanthe radial distance between the inner ends thereof and said surface.

9 remain in the position shown. The effect of this STANLEY M. UDALE. g

